高能天体物理现象

Thermonuclear (Type I ) X-ray bursts from accreting neutron stars offer a means to determine neutron-star (NS) mass ($M$) and radius ($R$) and thereby probe the properties of matter at supranuclear density. A subset of these events,…

We report the discovery of the first transient relativistic iron K{\alpha} line in an Active Galactic Nucleus (AGN) J1047+5907. The line was detected 21.5 days (rest-frame) after an X-ray coronal flare observed in 2008 and it exhibits…

We present a comparative analysis of supernova remnant Cassiopeia A based on two deep, narrow-band images covering the [Fe II] 1.644um + [Si I] 1.645um lines obtained in 2013 and 2020 with the same instruments on the UKIRT 3.8m telescope.…

In this paper we present a newly developed GRPIC code framework called FPIC, providing a detailed description of the Maxwell-equations solver, of the particle ``pushers'', and of the other algorithms that are needed in this approach. We…

We present the results of three-dimensional magnetohydrodynamic (3D MHD) simulations of the plasma flow structure in the vicinity of a compact cluster of young massive stars. The cluster is considered at the evolutionary stage dominated by…

Long Period Transients (LPTs) are a recently identified class of sources characterized by periodic radio bursts lasting seconds to minutes, with flux densities that might reach several tens of Jy. These radio bursts repeat with periodicity…

We present a spectroscopic analysis of XMM-Newton and NuSTAR observations of the 'complex' NLS1 PG 1535+547 at redshift $z=0.038$. These observations span three epochs: 2002 and 2006 with XMM-Newton alone, covering the $0.3-10$ keV energy…

Fast reconnection in magnetically dominated plasmas is widely invoked in models of dissipation in pulsar winds, gamma-ray flares in the Crab nebula, and to explain the radio nanoshots of pulsars. When current sheets evolve reaching a…

In this paper, we compute a full set of neutron star magnetosphere structures from the basic vacuum regime to the dissipation-less force-free regime by implementing a resistive prescription for the plasma. A comparison to the radiation…

We present a timing analysis of \textit{Insight}-HXMT observations of the black-hole X-ray binary Swift J1727.8$-$1613 across a bright soft X-ray flare on 2023 September 19 (MJD 60206). At the peak of the flare, the source undergoes a brief…

Time-variable propagation effects provide a window into the local plasma environments of repeating fast radio burst (FRB) sources. Here we report high-cadence observations of FRB 20240619D, as part of the HyperFlash and \'ECLAT programs. We…

Classical novae in the Milky Way have now been well-established as high-energy GeV $\gamma$-ray sources. In novae with main-sequence companions, this emission is believed to result from shocks internal to the nova ejecta, as a later fast…

Our understanding of the elusive radio-pulsar emission mechanism would be deepened by determining the locality of the emission. Pulsars in which the two poles interact can potentially help solve this challenge. We here report the discovery…

Gamma-Ray Bursts (GRBs) are the strongest explosions in the Universe, and are powered by initially ultra-relativistic jets. The angular profile of GRB jets encodes important information about their launching and propagation near the central…

Here we report on a new survey for pulsars and transients in the 10 pc region around Sgr A* using the Effelsberg radio telescope at frequencies between 4 to 8 GHz. Our calibrated full-Stokes data were searched for pulsars and transients…

TeV haloes are extended sources of very-high-energy gamma rays found around some middle-aged pulsars. The emission spanning several tens of parsecs suggests an efficient confinement of the ultra-relativistic lepton pairs produced by pulsars…

The pulsar J0537$-$6910 undergoes spin-up glitches more frequently than any other known pulsar, at a rate of roughly thrice per year. Its glitches are typically large and accompanied by spin-down rate changes $\Delta\dot\nu$ that partially…

Recent observations presented in Cendes et al. (2024a) show that optically selected tidal disruption events (TDEs) commonly produce delayed radio emission that can peak years post-disruption. Here, we explore the multi-wavelength properties…

Large sinusoidal variations in the radio light curves of the blazars PKS J0805$-$0111 and PKS 2131$-$021 have recently been discovered with an 18-year monitoring programme at the Owens Valley Radio Observatory, making these systems strong…

Context: Despite more than half a century of research, the dominant radiation mechanism of gamma-ray burst (GRB) prompt emission remains unsolved. Some progress has been made through the analyses of the observational spectra of Swift/BAT,…